One piece of advice I’ve seen is to write constantly. Another piece of advice I’ve seen is to just get it all out on the page and not worry about how it turns out, to fix it in the editing stage.
Except, I can’t help but go back and overthink it. If I write a section or piece, I’m constantly revising as I go along, reworking a sentence or scene or even the word choice as I write. Most recently, I had put myself to a challenge to write 500 words a day (I’ve already failed). I wrote a scene for a story I’d like to work on, but then next day I looked it over and didn’t like it. So I deleted it, and then thought some about what to do instead, and then didn’t write anything more than that.
If I’m being paid to write it, I’ll see if the customer likes how it turned out. If so, publish it and move the fuck on.
If I’m writing it for my own benefit and I don’t like how it turned out … then I go back and edit it or completely rewrite it until I do like how it turned out. Writing is rewriting.